Roughing tool for shoe parts



Oct. 18, 1932. c. A. ROBINSON 1,332,921

ROUGHING TOOL FOR SHOE PARTS Filed oct. 5. 1930 Patented Oct. 18, 1932 UNITED STATES PATENT OFFICE CHARLES ARTHUR ROBINSON, OF SALEM, MASSACHUSETTS, ASSIGNOR TO UNITED SHOE MACHINERY CORPORATION, OF PATERSON, NEW JERSEY, A CORPORATION F NEW JERSEY ROUGHING TOOL FOR SHOE PARTS Application Vinea october 3, 1930. seriaiivo. 486,182.

This invention relates to roughing tools and is particularly concerned with a novel and improved blade for tools for roughing shoe parts, an example of a tool in which my improved roughing blade may be used advantageously being disclosed and claimed in the prior a plication for patent to George Goddu, erial No. 423,204, filed January 24, 1930.

Roughing tools of the type of that shown in the said prior application have a considerable number of removable, toothed blades which must be replaced with new ones when the cutting or abrading teeth become so worn that they no longer out effectively.

It is an object of the present invention to provide a roughing tool with blades having a much longer life than those heretofore available, at little or no increased cost of manufacture, thereby effecting a substantial economy in the cost of using such tools.

With this object in view, an important feature of the invention resides in a blade having a plurality of groups of teeth capable of selective use, so that each group is capable of being used after another has worn out. This may be accomplished simply and economically by making the blade approximately polygonal and providing a group of teeth at each side of the polygon. Y In the illustrated embodiment of the invention the blade vis approximately square, there being four groups of teeth which may be presented alternatively in operative position. s

In accordance with a further feature o the Vinvention a roughing blade may be made reversible, so that when the teeth are chilled by wear the blade may be reversed and a further period of use secured by using what were originally the back faces ofthe teeth. This reversibility may be attained by making the blade symmetrical in shape in respect to its mounting so that when it is turned over it will present the same operating contour as before.

By combining the above described features a roughing tool is produced which has several times the length of useful life of those heretofore known, without a corresponding increase in the cost of manufacture.

rIhe foregoing and other features of the invention, and advantages to be derived from its use will be better understood and appreciated from vreading the following detailed description of a practical embodiment thereof in connection with the accompanying drawing, in which Fig. l is a view in elevation of aroughing tool with its cover plateremoved; and

F ig. 2 is a sectional view, taken upon the line II-II of Fig. l.

In the drawing, the tool is illustrated as operating to produce a roughened or abraded surface upon the overlasted portion 12 of the upper of a shoe 14 mounted upon a -last 16. The usual innersole over which the margins of the upper are lasted is shown at 18, and the illustrated operation is for the purpose of preparing the shoe bottom for the reception of cement by which an outer sole is to be attached to the shoe.

The roughing tool is mounted upon the reduced end portion 20'of a shaft 22 which may be rotated at a suitable speed by any desired means, the tool being secured in posivtion upon the shaft by a washer 24 and a nut 26 threaded upon the end of the shaft.

The tool itself comprises a disk 28 having a hub 30 bored to fit snugly upon the reduced end portion 20 of the shaft 22, and a second disk or cover plate 32 which is tted to the hub 30 and securedthereto by screws 34. A

Groups of stiff, rigid, abrading blades 36 of steel or other hard metal are arranged side by side in stacks and hung loosely upon pivot pins r38 mounted in the ldisk 28. The blades are approximately square and each is provided with four holes 39 of a size to fit the pivot pins'38. Each of the blades is also provided with an opening 41,l and through the openings of all the blades of each group passes a stop pin 42. The stop pins 42 are headed, as shown at 44, and are also mounted inthe disk 28,being held therein by a retaining plate 46 secured to the hub'portion of the disk by screws 48. The cover disk or plate 32 is provided with holes to receive the ends of the pins 38, 42 and is maintained in proper register by a dowel pin 50 also secured in the hub 30.

The four edges of each of the square blades 36 are provided respectively with groups of transverse teeth l designed to abrade the surface of the work smoothly and uniformly. The pins 42 serve as limiting stops to prevent excessive outward movement of the blades under the influence of centrifugal force as the tool rotates. As shown, the surface of each pin 42 is concavely curved longit-udinally of the pin, as illustrated at 52, so that the toothed abrading portions 5l of the blades, when thrown outward by centrifugal force, assume collectively a convex curvature transversely of the tool, as .illustrated at 54.

It will be seen that the di sks'QS, 32 constitute a rotary carrier upon which the abrading blades are loosely pivoted to permit them to be thrownoutward by centrifugal force as the carrier rotates and that the pins 42 constitute stop means for limiting the outward throw of the blades relative to the carrier.

The blades 36are arranged to engage an annular yielding backing member or cushion 58 if the work is pressed forcibly against the toothed outer edges of the blades. rlhe backing member 58 may conveniently consist of a ring of rubber surrounding the hub and Vsecured in position by the disks 28, 32.

In operation the tool is kept in rapid rotation and the bladesare thrown outward by centrifugal force to positions determined by the stop pins 42. IVhen the work is presented to the tool it may be pressed lightly against the teeth 5l in which case only a very thin layer of material will be removed, the blades yielding individually so that they collectively conform to the shape of the surface being operated upon and treat it evenly and uniformly. By reason of the normally convex curvature of the collective abrading portions of the blades, as shown at 54, the tool is able to follow such curves as are found in the bot-- tom of a shoe with a minimum of difference in the extent to which the individual blades are required to yield with a consequent advantage in respect to theV ease and certainty with which a uniform surface is produced on the work.

If a more vigorous abrading action is required the shoe may be pressed more forcibly against the tool, the abrading blades engaging the yielding backing member 58 which will permit them, while operating more forcibly, still to conform to the shape of the surface being roughened. When the outwardly facing groups of teeth 5l become dull from use the cover plate 32 may easily be removed, permitting the blades to be lifted off their pivot pins, turned through a quadrant and replaced with a new set of teeth in operative position. Each blade thus gives four times as much service as a blade having only one set of teeth; but the life of the blades is still further increased by making them symmetrical and reversible so that when all the teeth are dulled by wear the blades may be turned over and a further period of use secured by using what were originally the back faces of the teeth.

My improved roughing tool, in which the above described features are combined, has several times the length of useful life of those heretofore known, although the cost of manufacture is little, if any, greater.V

Having described the invention, what is claimed as new and desired to be secured by Letters Patent is:

l. In a roughing tool for shoe parts, an approximately polygonal abrading blade having a group of teeth at each side of the polygon.

2. In a roughing tool for shoe parts, an abrading blade having transverse work vroughing teeth, said blade being symmetrical and reversible to permit both the front and back faces of the teeth to be used.

3. In aroughing tool for shoe parts, a symmetrical abrading blade having a plurality of groups of selectively usable transverse teeth, said blade being reversible to permit both the front and the back faces of the teeth of each group to be used.

4. In a roughing toolv for shoe parts, the combination of a rotary carrier and a blade having a plurality of groups of abrading teeth any one of which groups of teeth may be presented in operative position, said blade being loosely mounted to permit it to be thrown outward centrifugally by rotation of the carrier regardless of which group of teeth is in operative position.

5. In a roughing tool for shoe part-s, the combination of a rotary carrier, a pivot pin on said carrier, a stop pin on said carrier, and a four-sided abrading blade loosely vmounted upon the pin, said blade having a group of teeth on eachV of its four sides, a pivot hole fitting said pin adjacent to each group of teeth and a central hole larger than the stop pin, through which central hole the stop pin passes regardless of which pivot pin hole contains the pivot pin. l

6. A symmetrical, approximately square,

abrading blade for a shoe part roughing tool,

said blade having a group of teeth along each of its four sides and a hole, arranged to receive a mounting pin, adjacent to each group of teeth.

In testimony whereof I have signed my name to this specification.

` oHARLns ARTHUR ROBINSON. 

